Broaching machine



March 7, 1944e .1. w. PoDEsTA BROACHING MACHINE Filed Aug. -2, 1940 '7 Sheets-Sheet 1 wwn--vdllw r .H

INVENTOR. J5 77,27/ Il pode.

March 7, 1944- J. w. Pom-:STA

BROACHING MACHINE Filed Aug. 2, 1940 '7 Sheets-Sheet 2 vllll. Il

INVENT OR.

March 7, 1944- J. w. PoDEsTA BRoAcHING MACHINE Filed Aug. 2, 1940 '7 Sheets-Sheet 3 1N VENTOR.

March 7; 1944. J. w. PoDEs'rA 2,343,420

BROACHING MACHINE Filed Aug. 2, 1940 v sheets-sheet 4 INV ENT OR.

March 7, 1944. J. wypODESTA 2,343,420 I BROACHING MACHINE4 y Filed Aug. 2, 1940 l 7 Sheets-Sheet 5 March 7, 1944. J. w, PODESTA 2,343,420

BROACHING MACHINE Filed Aug. 2, 1940 7 sheets-sheet e l T l INVENTQIL March 7, 1944. L W'PODESTA 2,343,420

BROACHING MACHINE Filed Aug. 2, 1940 "7 Sheets-Sheerl 7 BYCQQJ Patented Mar. 7, 1944 entre John W.' Podesta; Ann Arbor, Mich., assignorv'to American Breach .at Machine Co., Ann Arbor, Mich., a corporation of Michigan Application Augusta, 1940', seria-1 No. 349,430

i C1. fio- 33) 25 Claims.

The invention relates generally to breaching machines and more particularly to a breaching machine having a shiftable work support operable to move work pieces from aremete leading position to a position to be acted upon by the tools. It is the general object vof the invention te provide a new and improved breaching ma chine of this type. Y

Another object isl to provide a broachingmachine having a breach actuating rain with avv breaching and return stroke, an indexable werk support With a loading position, a workingpesition and a work discharge position, and means automatically operable to index the Work support to its Work discharge position at the end of the breaching stroke of the ram and te discharge the Work during the return stroke of the ram.l

Another object is to provide a breaching machine having a breach actuatingl ram with a breaching and a return stroke and an indexabl'e work support with a loading position, a Working position and a Work discharge position,` in Which indexing of the Werk support to Werk discharge position is effected automatically at the end of the breaching stroke of the ram and in Which completion of the indexing of the werk support initiates the return stroke of the ram and the discharge of the work.

A further object is to provide a breaching Ina-l chine having an indexable rotary Work table with diametrically eppositely'dispesed Work supports en the table permitting an operator standing at the front of' theV machineto load one of the supports while the machine isacting on Work pieces in the otherv support, and means for index-- ing the table through quarter revolutions and for automatically discharging the nished Work when the table is indexed 90v from working pesition. i

Still a further object is to provide a; breaching machine having a Work tableindexable te a loading position, a werking position and an un loading position, tiltable Work supports on thetable yieldably urgedte a normal Work supportingy position, and means coeperable with a work sup-- port when in unloading position to effect tilt ing thereof to discharge the work.

Another object is to provide an automaticpul1 breaching machine having automatic. breach handling mechanism and an indexable Worksupport which carries the Work blanks tol the breaches for the breaching operation and thereafter carries the Work blanks to a discharge position. v

machine with a breach yactuating ram having a breaching tool holder at one end thereof for releasably holding abroaching-tool, a movably mounted device forhandling the lbreach byits trailing end when detached from thebreach holder and an indexable Work support operable to move Work pieces from a loading position to a breaching position and thereafter te aposition intermediate the breaching and loading pesitions Whereinthe werk support is out of the Way of the breaches during a return movement of the breaches te the handling device;

Another object is toprovide a breaching Inachine having a breach actuating ram with a f breaching and a return stroke and a rotary indexable table with ydiametrically oppositely'dis'- posed Werk supports,`the table being indexable through a rst quarter revolution at the end of the breaching stroke te carry the finished Work to a discharge position and to remove the werk support from the path of the returning breaches; and indexable through afsecond quarter revolution at the end of the return stroke ofthe ram to present a new work blank to the breaches Still another object of the invention is teprovide in lsuch a machine anew and improved means for indexing the werk support, agmean's for discharging the finished work pieces from the Work support and nevel mechanism forl actuating and controlling the movement and tim-I ing'ef-the various parts of the machine. l j

Yet a further object is to provide a'breaching machine with abroach actuating ramhaving a breaching tool holder at one end thereof for re` l. leasably holding a breaching tool and a. device for handling the breaching tool by its trailing end when detached from the'brach *helder in cluding a head having detent means for releasablyhelding a breaching tool, the head in turn 'being releasablyV held inthe-device.

Other objects and advantages will become apparent from the following detailed'description taken in' connection with the accompanying drawings, in which:

Fig; 1 is a side view partially in elevation and partially in section of a broachingmachine embedying. the features of the invention.

Fig. 2r is a front elevational view of the 'machine shown in Fig. 1, but with the Werk supporting b ed and the driving mechanism contained therein removed. i n

Fig. 3 `is a greatly enlarged fragmentary vertical." sectional'view taken approximately along the Yet another object is to rprovide va breaching line S-SefFig. 2;

Fig. 4 is a plan view showing the work supporting table in position for loading and broaching.

Fig. 5 is a fragmentary view partially in plan and partially in section taken approximately along the line 5-5 of Fig. 1 and showing the Work supporting table in work discharge position.

Fig. 6 is a fragmentary front elevational view of that portion of the machine housing the work supporting table and table driving mechanism.

Fig. 'I is a greatly enlarged vertical sectional view taken approximately along the line 'I-I of Fig. 5 and showing the Work supportsl in dis-` charging position. y

Fig. 8 is an enlarged horizontal planview of the work supporting table drive mechanism, the table proper being removed.

Fig. 9 is an irregular vertical sectional view, on the same scale as Fig. 8, of the work supporting table and its driving mechanism, the table being in diametrical section, while the lower portion of the figure is broken away to a lesser depth.

Fig. 10 is a horizontal sectional view greatly enlarged, taken approximately along the line Ill--I of Fig. 1.

Fig. 11 is a vertical sectional view taken approximately along the line II-II of Fig. 10.

Fig. 12 is a diagrammatic view showing the hy draulic circuit and control devices.

Fig. 13 is a diagrammatic view of the electrical control crcuit.

While the invention is susceptible of various modifications and alternative constructions, it is here shown in the drawings and will hereinafter be described in a preferred embodiment. However, it is not intended that the invention is.

thereby to be limited to the specific disclosure made. On the contrary, it is intended to cover all modifications and alternative constructions falling Within the spirit and scope of the invention as defined in the appended claims.

For purposes of disclosure, the invention is here shown and will hereinafter be described as embodied in a broaching machine of the internal, pull-down type. Such a machine comprises generally an upright column I hawng formedv in the front thereof (see Figs. 2 and 5) vertical ways I6 in which is reciprocable a main broach actuating slide i1. Disposed in front of the column I5 and extending upwardly approximately one-half of the height of the column is a bed i8 on which is mounted a work supporting means I9. This means includes a stationary beam 20 and an indexable work supporting table 2| which is loaded by an operator standing in front of the machine, and is operable to carry the work from the loading position first to a broaching position, where it is acted upon by the broaching tool, and there-` after carries the work to a discharge position where the work is automatically unloaded. Broach handling mechanism, generally designated 22, is provided and functions to support the broaching tool 'above the work support during the presentation of a new work blank and to initiate passage of the tool through the work blank. Suitable driving means for the main slide, the work supporting table andA the broach handling mechanism are, ofcourse, provided and are located within the bed I8 or the column I5. l

The machine is automatic in operation, and to that end control means is provided for governing the operation of the various elements to assure their functioning in proper sequence, Briefly, the machine functions in the following manner: The machine is initially started and :li

nally stopped manually by the operator, all other cycles of operation automatically repeating. In a cycle of operation, the broach handling mechanism rst moves downwardly to pass the breaching tool through the work and into engagement with the main broach actuating slide, whereupon the main slide moves downwardly to pull the vbroach' through the work. During the breaching operation, the operator loads a new work piece onto the table 2l and, upon completi'on of the breaching operation and while the main slide remains down. the table 2| is automatically indexed through 90 to carry the iinished'work piece to discharge position and also to free the path permitting the breaching tool to be returned to normal position supported by the broach handling means 22. Completion of the indexing of the table 2l initiates the return movement of the main slide and as an incident to such movement the finished work piece is discharged. Upon return of the broaching tool to normal position, the table 2l is again indexed. thereby presenting new work pieces to broaching position and the machine is ready for the cycle to be repeated.

The main broach actuating slide il is, as stated, reciprocable vertically in ways IB formed in the front face of the column I5. This slide herein is driven hydraulically by a hydraulic motor 24 of the reciprocatory type comprising a cylinder 25 and a piston 26 (see Figs. l, 3 and 5). The cylinder 25 is formed integrally with the slide I1 to form a ram, while the piston 25 is r stationary having its rod rigidly anchored at its upper end in the top of the column I5. The piston rod comprises an inner hollow pipe 21 (see Fig. 12) which extends through the piston 26 to supply hydraulic fluid to the head end of the cylinder, and an cuter larger and concentric pipe 28 which forms van annular passage 29 by which fluid is supplied through apertures 30 located near the piston 26 to the rod end of the cylinder. At its lower end, the slide II is formed with an integral, forwardly projecting bracket 3| carrying a broaching tool pull head, generally designated 32.

The pull head 32 is a multiple head consisting of a plurality, in the present instance four, individual heads of the general character disclosed and claimed in the Lapointe Patent N o. 2,027,486. Each of the individual heads, as best seen in Fig. 3, comprises an elongated nipple 33 threaded into the bracket 3I and adapted to receive releasably one end ofV a breaching tool 34 conventionally formed with an annular groove 35 near the end thereof. Surrounding the nipple 33 and slidable longitudinally thereof is a sleeve 35 urged outwardly of the nipple by a compression spring 31 and limited in its outward movement by an annular shoulder'38 formed on the nipple near the outer end thereof. This sleeve controls a plurality of locking'plungers 33 slidable radially of the nipple 33. To effect control over the plungers 39, the sleeve 36 is formed with an annular groove 40 internally thereof, which when beveled, as clearlyseengn' Eig. 3. The; pull heart 32 is at all times disposed below the tstationalybeam 2i) which is formed in its underneath side with a recess or channel 4.! to accomodate the upper end of the nipples 33. Adapted to strike trip plates 42 bolted to the underneath side of the beam 2t, however, as the pull'headapproaohes the position shown in Fig. 3, is anfoutwardly projecting flange 43 formedl onv the sleevelfand by means of which the sleeveis shifted against vthe action of the springI 31 to release -th'eplungers SSL The end of the slide il opposite the bracket'Si is formed with a plurality of guideways 4t' in which is recip'rocable an auxiliary slide 45 constituting a part of the broachh'andling mechanism; This slide carries a vbracket 46 in turn carrying four individual tool receiving heads. One of such heads is shown in section in Fig. 3 and comprises a sleeve 4l having an axiallbore t8 in `which the upper end of the broachingtool Mis adapted. to be received. The sleeve 4l, as clearly shown in Fig. 3, is received in a stepped vbore 4S" in the bracket 4t, the bore being stepped to form an annular shoulder 45". Adapted to engage this shoulder to prevent relative movement of the parts in one direction is a shoulder 4T formed on the sleeve. The tool is yieldably retained'in the sleeve 41 through a dog 49 pivotally mounted in the sleeve 4l and adaptedtoproject into a groove 59 in the upper end o-f thebroaching tool. Yieldably urging the dogltS into engagement with the groove is a spring pressed plunger 5l The groove 5i! in this tool has beveled side walls and the dog has a beveled nose so that upon the. application of a certain pull on. the tool .the dog will be camrned out ofthe groove. Asa safety measure, the sleeve 4l is` in turn yieldably retained inthe bracket #it and to that end there is mounted in the bracket d a radially movable spring pressed detent 52 adapted to engage in a notch 52 formed in the outer surface of the sleeve 4'5. The notch 52 has one side wall beveled so as tolpermit the sleeve di to move upwardly should the broachng tool for any reason fail toenter the vbore 48 or project too far into the bore. A limit stop in the form of a screw 53 is mounted in the end of the bore it opposite the end through which the broaching tool enters the bore to provide an adjustable limit against which the end ofthe breaching tool may abut. e

Actuating the slide 45 of the broach handling mechanism is a hydraulic motor, generally designated 55 (see Figs. 1 and 3) which is of the reciprocatory type and comprises a cylinder 5t anda piston 5l. As here shown. the piston 51 forms the stationary element'lo the motor and toithat end is, through the medium of a double piston rod, anchored to the column i5 at the bottom thereof. An internal piston rod 58 (see Fig. 12.)- extends through the piston 5'! so as to supply iuid to the head end of the cylinder, while an outer, larger and concentric rod 59 forms an annular passage for conducting uid through ports 6l to the rod end of the cylinder. The upperend of the cylinder 5S is connected by an adjustablerod 52 to the slide t5 of the broach handling mechamism. The motor 55 is disposed immediately in front of the main slide orrain il -and passes freely through a bore 3i provided in the` bracket Si for that purpose. Preferably av shield. 32" extending upwardly from the bracket r3l is also provided. A positive stop for both the rami and the broach handling mechanismv is provided. This takes the fomn oa brackett".projecting fmmthe communi-5 'neai."g itsbase i Tlicibracbet properrfcrms the. stop for the ram.v while an.

onwardV extension: 62"' forms the, Stopfor the:

cylinder 56.

The slidetof the broach handlingmechanism always remains above the beam 2U, While the `head 32 alwaysA remains below' the beam though projecting partially thereinto, as previously described. Beam. 2.0' is Yintegral'with the bed i3 to form a stationary part of the work supporting means, and` thepart. onv which the work rests and which bearsthel brunt of the strain during the broaching; operation. To that end, thebeain 26 is, of course,` provided with suit able apertures through whichthe breaching tools 313 pass andy in the present instance, is formed with louri such aperturesv (see Fig. 4)'. Each of the apertures (see 3) has' a bushingA 63 with an enlarged head 64.V Mounted over the heads of the bushings is a channel-shaped mem ber 65 (see particularly Figs. 3, 4 and 5) which is drilled'to have apertures coinciding with the bore in the bushings '53 and which has an enlarged and beveled end toaid the passage of the work blanks on top of the. member E5.

The work supporting means, as above stated, includes an indexable work table 2| which is circular and is mounted'for. rotation on a stub shaft Gl journaled inthe bed I8. Mounted on the table disposed. diam'etrically' opposite one another are two sets lof work supports, generally designated 68. Each such work support is composed of stationary means 69 formed on the top of` the` table 2l 'and a plate 'H3 pivoted on the v table at l l. The work supports Git are, of course,

designedto accommodatethe particular work blanks to be breached.' In the present instance, the machine is intended for the breaching` of connecting rods and hence the plate 10, as best seen in Figs. 4 and 5, is formed with four pockets 72 each designed to--hold' a connectingfr rod. It is tov be understood, *of course; that the plate 'Hl could be varied to accommodate different types of work blanks. Depending from each plate 'l0 is 1 a nger 1S which is engaged by a spring pressed plunger 14, in order normally-to retain the plate 10 in work supporting position which, in the present instance, is its horizontal position. Both the finger 73 and the table 2! vare beveled '(see Fig; 9) to permit the linger' 13 toA swing inwardly and thereby tilt the plate Ill to a position from which the work blanks will be discharged radially outwardly and'v downwardly (see Fig. 7).

In order that `work blanks'may be carried from a loading to a broaching position' and thereafter to a discharge position, all in timed relationand coordinated with the movements 'of the ram and broach handling mechanism for maximum efficiency, means is'provided for indexing the table 2l through quarter revolutions. This means in cludes a Geneva mechanism (Figs. 8 and 9) comprising a. disk I6 rigid with the bottom of the table El and provided'with. intersecting, diametri-- cal `and perpendicular' 'grooves l?. 'Adapted to engage in the groovesv 'Itis follower T8 carried by a quadrantfl'il rigid on .a shaft' '30'journaled'in the bed I8. Theshaft'il is: drivenfrozn a rotary hydraulic motor. #It through a worm 82 on a shaft coupled' to the-motorshai't '83 anda worm wheel ifl''xedon theshaft 843; It is to be understood, of course, thatft'he` diameter of the quadrant and of the disk'TG, aslwell as thespacing of the shafts 67 and Bil; issuch that upon-rotationof the quadrantf 'lrthe follower lv willenter one Yof .the grooves 11y vand operate therein to rotate the table through 90'and will thereafter leave the groove and, during the remainder of the revolution of the quadrant 19, return to initial starting position to enter the end of a groove 11 spaced 90 from the groove previouslyentered.

Means is also provided for positively' locking the table 2| in its various positions. To that end, the disk 16 is provided with four sockets 85, while reciprocably mounted in the bed I8 is a locking plunger 86 for cooperative engagement with the sockets 85. The plunger 86 is urged to locking engagement by a compression spring 81 and is disengaged from a socket 85 and held in disengaged position during the indexing of the table 2| through the medium of a cam follower 88, carried by the plunger, and a cam 89 carried on the underneath surface of the quadrant 19. The cam is of a length such that the plunger is with drawn prior to engagement of the follower 18 with a groove 11, and held withdrawn until the follower 18 has left the groove in the disk 1S.

The finished work pieces herein are automatically discharged after the table has been indexed to its discharge position (shown in Fig. as an incident to the return movement of the broaching ram. To that end, there is journaled in the bed I9 a shaft 93 extending from the rear toward the front of the machine. At its rear end, this shaft has secured non-rotatably thereto a lever 94 (Figs. 7, 10 and 11) carrying a follower 95 adapted to be engaged by a cam 96 carried by the main broach actuating slide l1. Extending coaxially with the shaft 93 is a shaft 91 connected with the shaft 93 through a coupling 98.` Non-rotatably mounted on the shaft 91 is a lever 99 carrying a follower |00 at its free end adapted when the shaft is rotated in a counter-clockwise direction, as viewed in Fig. '7, to strike the finger 13 to tilt the plate 10 of the work support for the purpose of discharging the work pieces. Also non-rotatably xed on the shaft 93 is a lever |0| which is engaged at its free end by a tension spring |02, the other end of which is anchored to the frame of the bed I8, and which serves to urge the shaft 93 and hence the arm 99 to an inactive position. The shaft 91 projects through the front wall of the bed I8, at which point it is formed with a pair of axially spaced grooves |03. Engageable in one or the other of these grooves is a, pin |04 yieldably urged inwardly and manually withdrawable to permit the shaft 91 to be shifted axially. When engaged in a groove |03, as shown in Fig. 10, the shaft 91 is coupled to the shaft 93, but when the shaft is shifted outwardly until the pin |04 engages in the inner one of the grooves |03 the shafts 91 and 93 are disconnected. A collar |05 prevents the shaft 91 from being pulled outwardly too far and the projecting end of the shaft has extending transversely therethrough a hand pin |06.

Hydraulic circuit means is provided for supplying fluid to the various hydraulic motors at the times and in the quantities and directions necessary to bring about the desired operation of the broaching machine. This hydraulic circuit comprises a main pumping unit ||0 composed of av variable delivery piston type main pump, of the general type disclosed and claimed in the Gunnar A. Wahlmark application, Serial No. 228,966, filed September 8, 1938, Patent No. 2,232,984, patented February 25, 1941, a charging or make-up pump, and a hydraulically shifted reversing valve all housed in the same casing. The pumping unit has a first port connected by a conduit I Il to the inner piston rod 21 of the hydraulic motor 24, a second port connected by a conduit II2 to the annular passage 29 formed by the outer piston rod 28, an intake port for the make-up pump connected by a conduit I I3 to a reservoir or tank T to draw from the tank fluid to compensate for the difference in volume of opposite ends of the cylinder 25, and a discharge port connected to the tank T by a conduit ||3.

An electric motor I|4 housed in the column |5 drives the pumping unit IIO continuously in one direction and reversal of fluid discharge from the pumping unit is effected by shift of the reversing valve, while variation in displacementl is eifected by adjustment of the stroke of the piston under the control of a hydraulic motor II 5. The motor ||5 and the reversing valve are in turn controlled by a pair of pilot valves IIS and II1 which are spring urged to a normal position and are shifted to actuated position by the energization of solenoid coils MD and MU, respectively. The valves IIB and II1 are connected in a pilot circuit which includes a conduit I I8 in which the valve IIB is interposed and a conduit I|9 in which the valve I|1 is interposed. These conduits connect at one end to the opposite ends of the reversing valve and at the other end join to form a common conduit |20 leading to the pressure source as will presently become apparent. Connected at one end to one end of the governing motor I|5 and joining at the other end with the conduit ||8 intermediate the pumping unit and the valve IIB, is a conduit I2 I, while a conduit I22 is similarly connected to the conduit I I9 and to the opposite end of the motor |I5 to supply uld to one end or the other of the motor I I5 in accordance with the shift of the valves |I6 and I|1. Exhaust fluid is returned to the tank through conduits |23 and |24. A suitable back pressure check valve I 25 is interposed in the conduit I I2 to permit free flow of the fluid when supplied to the rod end of the cylinder 25 for the purpose of effecting a return stroke, but which maintains the fluid discharged from the rod end of the cylinder under a predetermined back pressure to assure a uniform movement of the slide during a broaching stroke.

Fluid for actuating the motor of the broach handling mechanism and the indexing motor 8| is supplied, respectively, by pumps PH and PI of a double` pump unit |26 which also is continuously driven by the electric motor IIll. The pump PH has an intake port connected with the tank T through a conduit I21 and a discharge port connected by a conduit |28 to a reversing valve |29. 'I'he reversing valve I 29 is in turn connected by a conduit |30 to the inner piston rod 58 and by a conduit I 3| to the annular passage formed by the outer piston rod 59 of the motor 55. Relief valves |32 and |33 are, respectively, connected to the conduits |30 and I3| to permit discharge to the tank under abnormal 1 conditions, while also connected to the conduit |30 and communicating with the tank is a conduit |34 which includes a check valve |35 arranged to prevent flow to the tank but to permit fluid to be drawn into the head end of the cylinder 56 to make up the deficiency during the time that the slide 45 is raised by the main slide at a rate greater than the rate of fluid supply to the head end of the cylinder by the pump PH. A return conduit |36 leads from the valve to the tank T.

Shift of the reversing valve |29 is again eected hydraulically under the control of pilot valves of the coil R.' It will become apparent as the description of the circuit and ofthe operation of the machine proceeds that'the relays IR and 5R govern the indexing of the table, that the relay 2R controls the pilot valves governing the direction of fluid flow to the motor of the broach handling mechanism, that the relay 3R. controls the pilot valves governing the direction of fluid flow to the main slide motor, while relay 4R is a monitor or master relay.

The various solenoid and relay coils and the various limit and relay switches are connected in a control circuit shown diagrammatically in Fig. 13, which comprises a transformer Tr having a primary winding P connected to a high voltage source, and a secondary S having its ends connected to lead wires LI and L2.v Connected between the wires -LI and L2, in a plurality of minor or subcircuits, are the various switches and coils. A rst such subcircuit Sc includes in series the relay coil 4R, a normally open, manually actuable starting switch M, and a normally closed, manually actuable stop switch SS. Connected around the start switch M in a shunt circuit |60 is the switch 4Rf-A which forms a. holding circuit for the relay coil 4R. Connected in series to form a second subcircuit Sc2 are the switches BLS-A, ZLS-A, lR-A, 4R-B and the coil 5R of the 5R relay. Connected about the switches SLS- A, ZLS-A and IR-A is a shunt circuit 16| including in series the switches 5LS-'-A and SR-A. Connected about the switchrZLS--A is a shunt circuit |62 which includes the switch 4LS-A and connected about the switches IRf-A and 4R.-B is a shunt circuit |63 which includes a normally open, manually actuable switch |64 adapted for inch indexing of the work supporting table. The solenoid coil I and the switches SR-B and 5R-C are connected in series between the line wires LI and L2 to form a subcircuit Sc3. and a fourth subcircuit Sc4 is formed by the series connection of the switches ILS-A, |R-Y and the lR-U coil. A fifth subcircuit S05 includes in series connection the coil lR-L and switches IR-X and 1LS-A and includes a shunt circuit |65 connected around the switch IR-X and the coil IR-L having in series the switches SR-A and ZR-X andthe coil 2R-L. A sixth subcircuit ScE includes in series the switches |LS-B, 21S-B, IR--B and 2BA-Y and the coil .2R-U. Connected about the coil 2RU and all the switches save ILS-B is a shunt circuit |66 which includes in series the switches 4R-D and 4R-E. Connected between these last named switches in four parallel circuits are the solenoid coils SD, SU, MU and MD for the valves |31, |38,

| |1 and I6, respectively. In series with the coilA SD are switches SLS-A, 2RB and 2R-C. In series with the coil SU are the switches 2LS-C, 2R-D and 2R-E. In series with the coil MU are the switches ELS- A, 3RB and JR-C. In series with the coil MD are the switches ILS-C, 3ft-D and 3ft-E. A seventh subcircuit Sc1 is formed by the series connection between the line wires Ll and L2 of the switches SLS- A, 2R-A and `llif--X and the coil SR-L, while an eighth and final subcircuit Sc8 includes in series connection the switches 4LS-B, IRf-C and SR--Y and the coil :iR-U.

VIn order better to understand the sequence of movements of the broaching machine, aswell as the functions of the various Vswitch devices, valves, and so forth, -the voperation of the machine willbe described briefly. For that purpose, let-it be assumed that the machine is idle in its normal starting position, that is, with the slide 45 of the broach handling mechanism and the main broach actuating slide both in their uppermost positions, and with the table 2| disposed with one work support in the broaching position, while the other work support is at the front of the machine where it can be loaded by the attendant. It is to be assumed further that unnished work blanks are mounted in the work support which is in breaching position. Under these conditions the limit switch device 21S will be tripped by the dog D| on the slide 45, the device BLS will be tripped by the dog D2 on the main slide, switch device SLS will be tripped by the arm |56, and switch device BLS will be tripped by the rod |51 of the work support tilting mechanism. The other switch devices will be in their normal position, relays 4R and 5R will be deenergized and all their switches open, all of the solenoid coils of the pilot valves will be deenergized, while the coils of the relays IR, 2R and 3R will valso be deenergized. In short, the switches will assume the positions shown in Fig. 13. To start operation, the attendant first starts the electric motor H4, which drives the pumps and then momentarily presses the start button M, thereby completing the subcircuit Scl to energize the 4R relay coil. Such energization of the coil 4R closes al1 of the switches of the 4R relay, among other things, to establish a holding circuit for the relay through the closure of the 4R-A switch and to complete the shunt circuit |66 which includes the coils SD and SU governing operation of the slide 45 through the closure of the switches 4R-D and 4R-E. As a consequence, the slide 45 is started on its forward or, in this instance, downward stroke, since a circuit is now completed through the switches ILS-B, .1R-D, sns-A, 21a-B, 2RC and 4R-E to energize the coil SD of the valve |31. Such shift of the valve |31, due to energization of the coil SD, causes the reversing valve |29 to shift so that fluid is supplied to the rod end of the motor 55. With the initial forward movel ment of the slide 45, the switch device ZLS is permitted to return to normal position, as a result of which its switches 2LS-A and ZLS--B are opened, while its switch ZLS-C is closed partially to condition the circuit including the SU coil, the later energization of which will initiate the return movement of the slide 45.

The slide 45 continues to move downwardly alone and relative to the slide |1 carrying its breaches through the work pieces, the stationary work supporting beam 2D, and into the pull head 32 disposed beneath the beam 20. At the time that the lower ends of the broaches are received in the pull head, the dog DI temporarily trips the switch device 3LS, thereby temporarily closing its switch 3LS-A which is normally open. Closure of the switch 3LS-A completes the subcircuit Sc1 temporarily to energize the relay coil 3Rf--L. Such energization of the SPV--L coil shifts the relay to open its BR--X switch deenergizing the SR-L coil, closing its 3R-Y switch preparatory to a subsequent energization of the SR-U coil, opening its 3R-B and 3ft-C switches and, above all, closing its 3RD and SRf-E switches. Closure of these latter switches completes a circuit energizing the coil MD of the pilot valve I6, which results in the pumping unit l0 supplying iluid to the head end of the cylinder 25 to initiate the breaching stroke of the main broach actuating slide. With the initial movement of the main broach actuating slide,

gization of the coil SD, the valve |31 is returned to normal position and the reversing vaiveV r|) is returned to neutral position stopping movement of the slide 45. The 'main slide, however, continues downwardly'to complete the Ilorca-ching operation and to withdraw the broa'ch from 'the broach handling heads of the rslide/|15 and'thro'ugh the work supports on the table -2`|. During the breaching stroke of the main slide, the dog D3 temporarily trips the switch device TLS, temporariiy to close its switch LS-A. Such closure of the switch lLS-A-completes the subcir cuit SCS to energize the relay coil |RL, resulting in the opening .of the relay switches iR-B, iR-C and iR-X and closingh of the switches iR-A and |R-Y. No immediate change takes place as a result, but the opening or closing of the certain switches Aserves to condition the circuits in which they are included for future operation, as will presently become apparent.

At the end of the breaching stroke of the main slide il, dog Dit trips the limit switch device 4LS, thereby ciosing its switches 4LSA and llLS--B' and opening its switch dLS-C. Opening of the switch IiLS-C deenergizes the coil MD of the pilot valve lli, thereby to arrest the breaching stroke of the main slide. Closure of the .switch tLS-B accomplishes nothing because switch 'i iR-C is open. However, closure of switch :ELS-A completes a circuit to the relay coil 5R through the switches 8LS-A, #ILS-A, IR-A and iR-B which are now all closed. Energize,-

tion of the coil 5R results in a ciosure of all of the relay switches SR-A, ERP-B and SPEC, the closure of iR-B and ilR-C resulting .in the completion of the subcircuit S03 .to Venergize the coii l. With the energization of the I coil, the pilot valve i5! is shifted in turn to eiect a'sliift of the valve Md, permitting flow of operating fluid to the indexing motor 8|, .resulting in commencemcnt oi' the indexing operation.

With the initial rotation of the shaft 8i! and the quadrant 'I9 nonrotatably xed therewith, the arm 55 releases theswitch device ELS to permit its reutrn to normal, resulting in a closure of its switch 5LS-A. Closure of this switch establishes a circuit for the coil 5R which is independent of the switch IR-A which will `presently be opened to place sole control over the indexing motor 8| in the switch device SLS. also, with the initial rotation of the .shaft Bil, the cam 39 on the quadrant 'i9 engages the cam follower t3 to withdraw the locking plunger 86 and at the saine time through the rod trip the switch device ILS. Tripping of the switch device iLS opens its switch ILS-B, rendering the MU and MD coils incapable of energization and closes iLS--A which completes the eubcircuit Sofi to energize the coil 'IH-JU. Energizetion of the lR-U coil of the relay IR opens ithe relay switches IR-Y and *IR- A, opening of the latter placing the switch MfS- Ain full control of the indexing motor, v'as above stated. `Enel`h gization of Vthe lR--Ucoil also're'sults in a cio# 4sure of switches IR-X and IR-B, whichy closure has no -eect save to condition circuits for future use, and closure of switch iRf-C conipletesthe subcircuit Sc energizing coilU of the relay 3R. Energization ofthe BR-U coil in turn effects closure of the relay switches 3RVA, SR-B, SR-C and Y:iR-X. However, closure of switches 3R--B and 3RC Adoes vnot initiate up ward movement of the main slide because ILS- B is still open. The switches BR-D, (iR-E and 3RYfare also opened-as a result of energization rof SR-U f When the indexing of the table 2! is complete, that is, when it has been rotatcd'throughQO" so as to carry the work blanks from broachin-g position to an unloading position, the cam 89 dicen gages from the follower permitting the plunger to engage with a socket in the table 2| to'lock the same and, incidental thereto, the switch device |LS is returned to normal position. rWith such'return to normal position, 'its switch ILSQA is opened and its switch |LS-B is closed. Opening of the switch ILS-A has no effect, but closure of the switch ILS-Bresults in completion ofthe circuit including the coil MU, which circuit had been previously Aconditioned by closure of the switches SRP-B andSR-C. Return movement of the main slide is now initiated, since the energization of the coil MU causes the pum-ping uni-t i!! under the control of the pilotl valve to supply fluid to the rod-end lof the cylinder v25. Some time after the initiation of thereturn stroke of the main slide, the shaft 80 'completes its revolution, causing the arm |56 4to trip device 5h23, thereby openingswitchrSLS--A and arresting operation of the indexing motor 8|. v i

With the initial return movement of the main slide, the switch device 4LS is permitted to return to normaL'resulting in the opening of its switches f 4LS-A and dLS-B, and vclosingV of its switch ALS- 0. Nothing transpires immediately i from this change, not evenrom the closure of LS-C, for the switches l3RD and Vlit- E are open. During the return movement of 'the main slide, the cam 9B carriedthereon engagesthe follower to vroel: shaft 93.*a'nd shaftlS'l and-the lever 59 normally coupled thereto. .Such :rocking ofthe shaft 9! tilts the `work support 70 which carries the 'finished Work pieces-causing the sameto be discharged. 4At the Asame time, rocking Vof .the shaft 93 throughthe rod |51 trips the .switchdevice SLS to openitsiswitch 8LS-A. The switch is, of course, 'again closed Aimmediately upon 1return of the worksupport to its .normal horizontal position. i i' During thereturn stroke, the main slid-e initially moves alone and relative to the breach handling lslide 45 .until the ,upperl ends .of `the broaches are restored to theheadsinthe v*slide 45.,

which Vtakes vplace about-the .Sametime that the key K on the mainsli'de-,errgages keyfKf on the slide 45. Prior to suchiengagement of the keyfK with kthe .slide 45, the dog rD'momentarily trips the switch -device 1LS,,temporarily closingv its switch ILS-A. Such temporay closure rof, the switch vvILS--A completes circuits ,energizing both 'the |R,-L and the 'Zlib-,I tcoils. Energizationof the |R-.L coil of the relay IR causesits switches |R-,B IR-.C and |R-X to be opened and jits switches |R-A and-|ReY to belQSed, butigno immediate change isfeifected. Energization'-iof '2R- L opens therelatr switches `Zhi-713,; 2R-+C `and '2R-X and closes the relay :switchesZlib-fel), 2R-E and 2R,Y. :Glosuref': off-thesswtches 2R-D and ZR-E completes a circuit to the coil SU of the pilot valve |38,- thereby effecting a shift in the reversing valve |29 insuch direction that iluid is supplied to the head end of the cylinder 56. The broach handling slide 45 and the main slide now move through their return stroke in unison.

With the initial return movement of the slide 45, the switch device BLS is, of course, released and permitted to return to normal, resulting in a closure of its switch SLS-A. Closure of this switch, however,` does not energize the coil SD since the switches ZR-B and 2Rf--C have previously been opened as a result of the energization of thelR-L coil. During the return movement of the slide 5, the dog DI also temporarily trips the switch device SLS, but, like the switch 9LS, is ineifective because the switch 2R-A is open at such time. The two slides continue in unison until the dog D2 trips the switch device ELS, effecting an openingv of the switch GLS- A. Because of the opening of the switch GLS- A, the circuit to the coil MU is broken and, with the deenergization of the coil, the pumping unit H discontinues supplying operating uid whereby the main slide comes to rest in its uppermost normal starting position. The slide 45 noviT continues in its return movement independently of the main slide and until its dog Dl trips the switch device ZLS.

With the tripping of the device ILS, its switch 21S- C is opened to deenergize the coil SU, resulting in a return of the reversing valve 129 to neutral position and cessation of flow of iiuid to the motor 55 of the broach handling mechanism bringing the slide 45 to a stop in its uppermost normal startingposition. Tripping of the device 2LS closes its switches 2LS-B and 2LS-A, closure of the latter serving to complete a circuit energizing the coil R. This results in closure of all of the 5R relay switches, namely SR-A, SR--B and SRf-C to again partially establish a holding circuitl for the relay 5R and to complete the subcircuit SC3 to energize the coil I. With the energization of the coil I, the indexing motor 8l is started, as previously described, and with the initial operation of the motor the switch device SLS is permitted to return to normal, while the switch device ILS is tripped. Return of the switch device BLS to normal closes its switch SLS-A to complete the holding circuit for the relay coil 5R. Tripping of the switch device ILS opens ILS--B again to render all of the solenoid coils on the pilot valves incapable of energization and closes ILS-A to energize lR-U. Energization of |RU opens IR-A to place 5R under the sole control of the switch SLS and closes IRf-B and lR-C to condition circuit to 2Rf-U. With the completion of the indexing of the table, that is, the rotation of the same through 90 which has now again placed one of the work supports in the broaching position, while the other is at the front of the machine ready to be loaded by the attendant, the table is locked and the switch device ILS returned to normal. Such return to normal opens its switch ILS-A and closes its switch ILS-B to complete the subcircuit S06 and energize the coil 2RU. Such energization of the coil opens the relay switches ZR-D and 'iR-E and closes the relay switches ZR-A, ZR-B and ZR-C. Closure of the latter two completes the circuit to the coil SD of the pilot valve '131, initiating a new cycle of operation of the broaching machine.

`Iclsim as myv invention:

1. An internal broachingmachine comprising, in combination, broach actuating mechanism including a slide having a broaching tool holder at one end thereof for releasably holding a broaching tool and means for actuating the slide through a broaching stroke and a return stroke, a movably mounted device for handling the broaching tool by its trailing end when detached from the broach holder, means for actuating said device, an indexable work support, means actuating said support to transport a work piece from a loading position to a broaching position and thereafter from the broaching position to a discharge position, and means automatically operable to govern the operations of said actuating means including means actuated upon completion of the broaching stroke to effect an indexing of said work support carrying the work to discharge position.

2. An internal broaching machine comprising, in combination, broach actuating mechanism including a slide having a broaching tool holder at one end thereof for releasably holding a broaching tool, and means for actuating the slide through a broaching stroke and a return stroke, a movably mounted device for handling the broaching tool by its trailing end when detached from the broach holder, means for actuating said device, an indexable work support, means actuating said support to transport a work piece from a loading position to a broaching position and thereafter from the broaching position to a discharge position, and means automatically operable to govern the operations of said actuating means including means actuated upon completion of the indexing to discharge position to initiate return of the broaching tool to the broach handling device.

3. An internal broaching machine comprising, in combination, broach actuating mechanism including a slide having a broaching tool holder at one end thereof for releasably holding a broaching tool and means for actuating the slide through a broaching stroke and a return stroke, a movably mounted device for handling the broaching tool by its trailing end when detached from the broach holder, means for actuating said device, an indexable work support, means for actuating said support to transport a work piece from a loading position to a broaching position and thereafter from the broaching position to a discharge position, and means automatically operable to govern the operations of said actuating means including means actuated upon return of the broach handling device to normal position to initiate operation of the actuating means causing an indexing movement of said work support carrying a new work; piece to broaching position.

4. An internal broaching machine comprising, in combination, broach actuating mechanism including a slide having a broaching tool holder at one end thereof for releasably holding a broaching tool, and means for actuating the slide through a broaching stroke and a return stroke, a movably mounted device for handling the broaching tool by its trailing end when detached from the broach holder, means for actuating said device, an indexable work support, means for actuating said support to transport a work piece from a loading position to a broaching position and thereafter from the broaching position to a discharge position, and means automatically operable to govern the operations of said actuating means including means actuated upon comnation, breach actuatingmechanism including l a slide having a breaching tool holder at one end thereof for releasably .holding a breching tool and means for actuating the slide through a breaching stroke and a return stroke, an indexable work support, means for actuating the werk support to move work pieces from a loading position te a breaching positionv and thereafter te a discharge position intermediate the breaching and loading. positions, means automatioally operable te govern the eperationsef said actuating means including means actuated as an incident to return of the breach te normal position to initiate operation of said work support actuating means to index said work support te move a werk piece thereon lto breaching position.

v6. In a breaching machine; breach actuating means including a slide having a Abreaching and a return stroke, an indexable work support shiftable te a loading, a breaching and a work discharge position, power means independent of saidv breach actuating means for indexing said werk support, control means for said power means operable when tripped to initiate indexing of the werk support fromv breaching te discharge. position, and means moving in timed relation with said slide engaging and tripping said control means at the end of the breaching stroke;

7. In a breaching machine, breach actuating means including a slide having a breaching and'a return stroke, an indexable werk support shiftable to a loading, a werking and anintermediate work discharge position, means operable to index the werk support te its discharge position at the end of the breaching stroke of the slide, and means operable upon a completion of the indexing movement te initiate the return stroke of the slide. Y Y

8. A breaching machine comprising, in combi'- nation, a breach actuating ram having a breaching tool helder at one end'thereet for releasably holding a breaching tool andvhaving a breaching stroke and a return stroke, an indexable werk support operable te move werk pieces from a loading position to a breaching position and thereafter te a discharge position intermediatethe breaching and leading positions, means including a locking pin for positively holding said werk support in indexed position,A means automatically operable te govern the movements of -said ram and said work support including means governed by said locking pin operating to prevent power driven movement of said ram while said pin is disengaged te free said support for indexing, said last mentioned means being operable upon reJ turn of said pin te locking engagement alternately te initiate return movement of said ram and la new cycle of *operation ef the breaching machine.

9.' A breaching machine comprising, in combination, a breach actuating ram having a breaching tool helder at one end thereof for releasably holding a breaching tool and having a breaching stroke and a return stroke, an indexable werk support operable te move' work pieces rfrom a leading position to a breaching position and thereafter te a discharge .positionv intermediate the breaching and loading positions, means including a locking pin for positively holding said Werklsuppert in indexed position, means autematically operable te govern the movements of said ram and lsaid workfsupport 'including mea-ns governed by said locking pin eperatingto'fprevent power driven movement of said ram while said pin is disengaged te free said support for indexing and te initiate return movement of said ram upon returnlef -said pin to locking engageme111; i i. 1

10. In a breaching machine, breach actuating means including a slide having a breaching and a return stroke, 'an indexableA work support shiftable te a leading, a .werking and werk'discharge position, means automatically operable to index the work support te itsfdischargev position at thelend of the breaching stroke of the slide andy te initiate the `returnstroke at the completien of the indexing, andmeansactuated during the return stroke of said slide te discharge the werk. i L N i 1l. In a breaching machine, breach actuating means including a slide having a breaching and a return stroke, an indexable werk table operable te carry a work blank from leading position `te breaching position and thereafter te discharge position, ra tiltable werk support carried by said table, means automatically operable at the end of the'breaching stroke of said slidelte initiate indexing of said-'table from breaching'te` werk operable when a work support is in discharge pesition-to engage and tilt the werk support to discharge the werk therefrom.I

12. In a breaching machine, a work supporting table indexable to a loading position, awerking position and an unloading position, a tiltable workA support en the table yieldab'ly urged te a normal work supporting position, and means ceoperable with the werk support when in unloading position te effect tilting thereof te discharge thework. l -f 13. In a breaching `machine,. a breach actuating slide, a Work supporting-table indexable te a loading position, a werking position and an unloading position, a tiltable werk support len' -the table yieldably urged te a normal work supporting pesitiena cam` mounted on said breach actuating slide, and means engaged and actuatedby saidcam during the return stroke of said 'slide te tilt said werk support when in unloading position te discharge the work therefrom. i 14. In a breaching machine, a breach actuating main slide/having a breaching tool-holder at one end thereof for' releasably holding a bre-aching tool, and-a devicefor handling .the breaching tool by its trailing Send when detached from the breach helder including a breach 4receiving member movable therein, detent means'carried by said member for -releasablyhelding a breaching tool and detent means mounted in said device engaging said member and yieldably retaining said member in said device for automatic release uponl application of excess force by the tool.

v15. In a breaching machine,l a breach actuating main slide having a breaching tool holder at body, an inner fmember having an axial bore adapted te receive an end of a breaching tool therein, said inner member being loosely received in said outer body for axial withdrawal, a deg pivoted in said inner member and adapted te project into the bore therein to engage means on the breaching tool, spring pressed means yieldably urging said dog inwardly, a notch on the external surface of said inner member, and a spring pressed detent in said body engaging the notch in said inner member releasably to retain the same.

16. In a machine tool, a rotary werk supporting table having a plurality of radially extending grooves epening through the periphery of the table and equally spaced angularly, means for indexing the table through angular amounts less than 180 comprising a quadrant mounted for rotation on an axis parallel with the axis of said table, a motor for driving said quadrant, a follower carried bysaid quadrant, said quadrant having its axis spaced from the axis of said table and said follower so spaced radially thereon as to engage in a, groove in said table during only a portion of a revolution of said quadrant, means for locking said table in its various positions gcomprising a plurality of sockets, one for each position, formed in said table and a locking plunger engageable with said sockets, and an elongated cam formed en said quadrant and operable prior to entry of the follower inte a groove te engage and Withdraw said locking plunger and te hold the same withdrawn until the follower again leaves the groove.

17. In a breaching machine a broach actuating slide, a werk supporting table indexable to a loading, a werking and a werk ldischarge position, a tiltable work support mounted on said table yieldably urged to work supporting position, means for tilting said work support when the same is in work discharge position comprisuing a. first rotatably mounted shaft, an arm nonrotatably fixed en saidshaft, a cam' carried on `said breach actuating slide, means normally rocking said shaft te position the arm `in the path ef said cam to rock said shaft during the return stroke of said slide, a second shaft coaxial with said first shaft, a second arm nen-rotatably fixed on said shaft and operable upon rotation to tilt said work support to discharge the work therefrom, a, clutch interposed between said shafts, said second shaft having limited axial vmovement permitting engagement or disen- .gagement of said clutch and projecting outwardly of the breaching machine for operation by `an. attendant, and means for holding the shaft in clutch engaged or clutch disengaged position. y18.,.1in internal "breaching machine compris- Aing, in combination, a stationary work support,

a breach actuating ram having a breaching tool Yholder at one end thereof and disposed to one side of the stationary werk support for releasably holding a breaching tool, means for actuating the ram, a movably mounted device disposed to the other side of the werk support for handling the breaching tool by its trailing end when detached from the breach holder, means for actuating said device, an indexable work support, a werk leading station, a breaching station and an unloading station intermediate the breaching and the leading stations, means fer driving said indexable Work support from station te station, control means initiating operavtion of said driving means to index said werk support, and means operable upon completion of the breaching stroke by said breach actuating ram to initiate operation of said driving means to index the werk support te unloading position where it is out of the path of the breach during the return to the broach handling device.

19. An internal breaching machine comprising, in combination, broach actuating means including a slide having a breaching tool holder at one end thereof for releasably holding a breaching tool, a movably mounted device for handling the breaching teel by its trailing end when detached from the broach holder, an indexable work support operable te transport a werk piece from a leading position te a breaching position and thereafter from the breaching position to a discharge position, driving means for each said slide, said handling device and said work support, control means for governing said driving means, and means actuated in timed relation to the movement of said slide operable upon completion of the breaching stroke to initiate operation of the driving means for said work support to carry the Werk to discharge position.

20. An internal breaching machine comprising, in combination, broach actuating mechanism including a slide having a breaching tool holder at one end thereof for releasably holding a breaching tool and means for actuating the slide, a movably mounted device for handling the breaching tool by its trailing end when detached from the broach holder, means ier actuating said device, an indexable werk support, means actuating said support to transport a werk piece from a loading position to a breaching pesition and thereafter from the breaching pesitien to a discharge position, control means for said actuating means including tripable devices for initiating or arresting operation of said actuating means, and means carried by said work support engaging, upon the work support reaching discharge position, a tripable device initiating operation of the actuating means effecting return of the broach actuating mechanism.

-from the broach holder, means for actuating said device, an indexable werk support, means for actuating said support to transport a werk piece from a leading position to a breaching position and thereafter from the breaching position to a discharge position, control means for said actuating means including tripable devices for initiating er arresting operation of the actuating means, and means actuated in timed relation with the movement of said broach handling device operable upon return of the breach handling device to normal position to engage a tripable device initiating an indexing movement of said werk support te carry a new work piece to breaching position.

22. An internal breaching machine comprising, in combination, breach actuating mechanism including a slide having a breaching tool holder at one end thereof for releasably holding a breaching tool and means for actuating the slide, a movably mounted device for handling the breaching tool by its trailing end when detached from the broach holder, means for actuating said device, an indexable work support, means for actuating said support to transport a Work piece from a loading position to a broaching position and thereafter from the broaching position to a discharge position, control means for said actuating means including tripable devices for initiating or arresting operation of said actuating means, and means actuated in timed relation with said Work support engaging, upon completion of the indexing movement carrying a new work piece to broaching position, a tripable device initiating operation of the actuating means for said device to start a new cycle of operation of the broaching machine.

23. A broaching machine comprising, in combination, broach actuating mechanism including a slide having a broaching tool holder at one end thereof for releasably holding a broaching tool and means for actuating the slide through a breaching stroke and a return stroke, an indexable work support, means for actuating the work support to move work pieces from a loading position to a breaching position and thereafter to a discharge position intermediate the broaching and loading positions, means automatically operable to govern the operation of said actuating means including tripable devices for initiating or arresting operation of said actuating means, and means actuated in timed relation with the Ybroach engaging, upon return of the broach to normal position, a tripable device initiating operation of the actuating means for said Work support t carry a work piece thereon to breaching position.

24. In a breaching machine, a Work supporting table indexable to a loading position, a Working position and an unloading position, a tiltable Work support on the table yieldably urged to a generally horizontal Work supporting position, and means cooperable with the Work support when in unloading position to effect tilting thereof from its horizontal position to discharge the work by gravity.

25. In a broaching machine, a broach actuating main slide having a broaching tool holder at one end thereof for releasably holding a broaching tool, and a device for handling the broaching tool by its trailing end when detached from the broach holder, including means for releasably holding a broaching tool comprising an outer body having a stepped bore forming an annular shoulder, an inner member received in said bore and having an annular shoulder engaging the shoulder in said bore to prevent relative movement between said outer body and said inner member in one direction, said member being adapted to receive an end of a breaching tool,

means for releasably holding a tool in said inner member, and detent means for releasably holding said inner member in said outer body against relative movement in the direction not restrained by the shoulders.

JOHN W. PODESTA, 

